<template>
  <div class="shopcart">
    <div class="content">
      <div class="content-left">
        <div class="logo-wrapper" @click="toggleList">
          <div class="logo" :class="{'highlight': totalCount > 0}">
            <i class="icon-shopping_cart" :class="{'highlight': totalCount > 0}"></i>
          </div>
          <div class="num" v-show="totalCount > 0">
            <Bubble :num="totalCount"></Bubble>
          </div>
        </div>
        <div class="price" :class="{'highlight': totalPrice > 0}">
          ￥{{totalPrice}}
        </div>
        <div class="desc">另需配送费￥{{deliveryPrice}}元</div>
      </div>
      <div class="content-right">
        <div @click.stop="pay" class="pay" :class="payClass">
          {{payDesc}}
        </div>
      </div>
    </div>
    <div class="ball-container">
      <div v-for="(ball, index) in balls" :key="index">
        <transition
          @before-enter="beforeDrop"
          @enter="dropping"
          @after-enter="afterDrop">
          <div class="ball" v-show="ball.show">
            <div class="inner inner-hook"></div>
          </div>
        </transition>
      </div>
    </div>
  </div>
</template>

<script>
import Bubble from 'components/bubble/Bubble.vue'

const BALL_LEN = 10
const innerClsHook = 'inner-hook'

function createBalls () {
  let balls = []
  for (let i = 0; i < BALL_LEN; i++) {
    balls.push({ show: false })
  }
  return balls
}

export default {
  name: 'Shopcart',
  components: {
    Bubble
  },
  props: {
    selectFoods: {
      type: Array,
      default () {
        return []
      }
    },
    deliveryPrice: {
      type: Number,
      default: 0
    },
    minPrice: {
      type: Number,
      default: 0
    },
    fold: {
      type: Boolean,
      default: true
    },
    sticky: {
      type: Boolean,
      default: false
    }
  },
  data () {
    return {
      balls: createBalls(),
      listFold: this.fold
    }
  },
  created () {
    this.dropBalls = []
  },
  computed: {
    totalCount () {
      let count = 0
      this.selectFoods.forEach((food) => {
        count += food.count
      })
      return count
    },
    totalPrice () {
      let total = 0
      this.selectFoods.forEach((food) => {
        total += food.price * food.count
      })
      return total
    },
    payDesc () {
      if (this.totalPrice === 0) {
        return `￥${this.minPrice}元起送`
      } else if (this.totalPrice < this.minPrice) {
        let diff = this.minPrice - this.totalPrice
        return `还差￥${diff}元起送`
      } else {
        return '去结算'
      }
    },
    payClass () {
      if (!this.totalCount || this.totalPrice < this.minPrice) {
        return 'not-enough'
      } else {
        return 'enough'
      }
    }
  },
  methods: {
    drop (el) {
      for (let i = 0; i < this.balls.length; i++) {
        const ball = this.balls[i]
        if (!ball.show) {
          ball.show = true
          ball.el = el
          this.dropBalls.push(ball)
          return
        }
      }
    },
    beforeDrop (el) {
      const ball = this.dropBalls[this.dropBalls.length - 1]
      const rect = ball.el.getBoundingClientRect()
      const x = rect.left - 32
      const y = -(window.innerHeight - rect.top - 22)
      el.style.display = ''
      el.style.transform = el.style.webkitTransform = `translate3d(0,${y}px,0)`
      const inner = el.getElementsByClassName(innerClsHook)[0]
      inner.style.transform = inner.style.webkitTransform = `translate3d(${x}px,0,0)`
    },
    dropping (el, done) {
      this._reflow = document.body.offsetHeight
      el.style.transform = el.style.webkitTransform = 'translate3d(0,0,0)'
      const inner = el.getElementsByClassName(innerClsHook)[0]
      inner.style.transform = inner.style.webkitTransform = 'translate3d(0,0,0)'
      el.addEventListener('transitionend', done)
    },
    afterDrop (el) {
      const ball = this.dropBalls.shift()
      if (ball) {
        ball.show = false
        el.style.display = 'none'
      }
    },
    toggleList () {
      if (this.listFold) {
        if (!this.totalCount) return
        this.listFold = false
        this._showShopcartList()
        this._showShopcartSticky()
      } else {
        // this.listFold = true
        this._hideShopcartList()
      }
    },
    pay () {
      if (this.totalPrice < this.minPrice) {
        return
      }
      this.$createDialog({
        type: 'confirm',
        title: '支付',
        content: `您需要支付${this.totalPrice + this.deliveryPrice}元`
      }).show()
    },
    _showShopcartList () {
      this.shopcartListComp = this.shopcartListComp || this.$createShopcartList({
        $props: {
          selectFoods: 'selectFoods'
        },
        $events: {
          hide: () => {
            this.listFold = true
          },
          leave: () => {
            this._hideShopcartSticky()
          },
          add: (el) => {
            this.shopcartStickyComp.drop(el)
          }
        }
      })
      this.shopcartListComp.show()
    },
    _hideShopcartList () {
      const comp = this.sticky ? this.$parent.list : this.shopcartListComp
      comp.hide && comp.hide()
    },
    _showShopcartSticky () {
      this.shopcartStickyComp = this.shopcartStickyComp || this.$createShopcartSticky({
        $props: {
          selectFoods: 'selectFoods',
          deliveryPrice: 'deliveryPrice',
          minPrice: 'minPrice',
          fold: 'listFold',
          list: this.shopcartListComp
        }
      })
      this.shopcartStickyComp.show()
    },
    _hideShopcartSticky () {
      this.shopcartStickyComp.hide()
    }
  },
  watch: {
    totalCount (newVal) {
      if (!this.listFold && !newVal) {
        this._hideShopcartList()
      }
    }
  }
}
</script>

<style lang="stylus" scoped>
@import "~common/stylus/mixin"
@import "~common/stylus/variable"

.shopcart
  height: 100%
  .content
    display: flex
    background: $color-background
    font-size: 0
    color: $color-light-grey
    .content-left
      flex: 1
      .logo-wrapper
        display: inline-block
        vertical-align: top
        position: relative
        top: -10px
        margin: 0 12px
        padding: 6px
        width: 56px
        height: 56px
        box-sizing: border-box
        border-radius: 50%
        background: $color-background
        .logo
          width: 100%
          height: 100%
          border-radius: 50%
          text-align: center
          background: $color-dark-grey
          &.highlight
            background: $color-blue
          .icon-shopping_cart
            line-height: 44px
            font-size: $fontsize-large-xxx
            color: $color-light-grey
            &.highlight
              color: $color-white
        .num
          position: absolute
          top: 0
          right: 0
      .price
        display: inline-block
        vertical-align: top
        margin-top: 12px
        line-height: 24px
        padding-right: 12px
        box-sizing: border-box
        border-right: 1px solid rgba(255, 255, 255, 0.1)
        font-weight: 700
        font-size: $fontsize-large
        &.highlight
          color: $color-white
      .desc
        display: inline-block
        vertical-align: top
        margin: 12px 0 0 12px
        line-height: 24px
        font-size: $fontsize-small-s
    .content-right
      flex: 0 0 105px
      width: 105px
      .pay
        height: 48px
        line-height: 48px
        text-align: center
        font-weight: 700
        font-size: $fontsize-small
        &.not-enough
          background: $color-dark-grey
        &.enough
          background: $color-green
          color: $color-white
  .ball-container
    .ball
      position: fixed
      left: 32px
      bottom: 22px
      z-index: 200
      transition: all 0.4s cubic-bezier(0.49, -0.29, 0.75, 0.41)
      .inner
        width: 16px
        height: 16px
        border-radius: 50%
        background: $color-blue
        transition: all 0.4s linear
</style>
